Fluid signal generator



Sept. 7, 1965 P. BAUER 3,204,652

FLUID SIGNAL GENERATOR Filed Dec. 28, 1961 FIG. I

24 12} j f fi 14 1 my I 1 Q 12- 2s 18 14-- FIG. 10.

l/VI/E/VTUR PETER BAUER ATTORNEY United States Patent 3,204,652 FLUIDSIGNAL GENERATOR Peter Bauer, 'Ambler, Pa., assignor to Sperry RandCorporation, New York, N.Y., a corporation of Delaware Filed Dec. 28,1961, Ser. No. 162,776 9 Claims. (Cl. 137-815) It is a further object ofthe invention to provide an improved fluid pulse generator adapted toproduce fluid pulses of variable time duration.

It is a still further object of the invention to produce an improvedfluid pulse generator adapted to produce fluid pulses at a variablerepetition rate.

According to the invention, means are provided to direct a fluid powerstream representing an output pulse to pass on opening in an enclosureto create a partial vacuum within the enclosure. When the vacuum withinthe enclosure reaches a certain level, the resulting pressure dropcauses the power stream to deflect into said enclosure. After thepressure in the enclosure rises to a certain level, the power stream isswitched back and resumes its original path of flow.

Further objects of the invention will become apparent upon reading thefollowing specification, together with the accompanying drawing, inwhich:

FIG. 1 illustrates a plan view, partly broken away, of a deviceaccording to the invention.

FIG. 1a illustrates an end view of the device shown in FIG. 1, withmeans for applying power fluid to the device.

FIG. 2 illustrates diagrammatically another embodiment of the device ofFIG. 1.

FIG. 3 illustrates diagrammatically still another embodiment of thedevice of FIG. 1.

Referring particularly to FIGS. 1 and 1a, a fluid operated device 10according to the invention is formed by three laminae 12, 14 and 16.Lamina 14 is positioned between laminae 12 and 16, and is tightly sealedbetween them by suitable means, such as screws or cement (notillustrated). The laminae 12, 14 and 16 may be of any metallic, plasticor other suitable material. For purposes of illustration, laminae 12, 14and 16 are shown as being of a clear plastic material.

The lamina 14 has a cut-out section, obtained for example, by means of acutting or stamping operation. The entire cut-out section is designatedas a configuration 18. The cut-out section or configuration 18 includesa fluid supply inlet 20, a fluid outlet 22 and a control chamber 24. Thefluid supply inlet 20 forms a constricted supply orifice 26,communicating with the outlet 22 and the control chamber 24. The termorifice as used herein includes an orifice, having parallel, convergingor diverging walls or any conventional shape. The supply inlet 20communicates with a bore 28 in lamina 16. The output end of fluid outlet22 may communicate with various control or utilization devices (notshown) to perform desired Work functions.

Bore 28 may be internally threaded to receive a tube 30 which may beexternally threaded. The end of tube 30, extending from lamina 16 isconnected with a source 32 of fluid under pressure. The fluid underpressure may be a gas or air, or water or other liquid. Fluid flowregulating devices, such as a valve 34, may be used in conjunction withthe fluid source 32, so as to supply a constant flow of fluidat adesired pressure. Such fluid regulating devices are of conventionalconstruction.

The control chamber 24 contains a piston 36 of planar form. The pistonis provided with rod 38 by means of which the piston may be moved todifferent positions within the chamber thereby determining its momentaryvolume.

Fluid flowing from source 32 and entering the device through supplyinlet 20 is, for the purpose of explanation,

assumed to be at a certain pressure above atmospheric pressure. As thestream of fluid is reduced in cross-sectional area in the orfice 26, itsvelocity increases. The fluid stream of reducedcross-sectional area,indicated by arrow 40, is called the power stream of the device. Thedesign of the device, i.e. the position of the outlet 22 with respect tothe control chamber 24, is such that, if no internal or external forcesare active on the power stream, it will travel longitudinally from theorifice 26 into the outlet 22 and exit, undisturbed in its motion, viathis outlet.

However, since the power stream passes the region 42, where the outlet22. and the control chamber 24 communicate, the control chamber 24 willbe partly evacuated. The pumping action taking place in the region 42 isgenerally called ejection pumping or jet pumping. As a result of thepumping action a presmre difference arises between the side of the powerstream facing the control chamber and the opposite side of the powerstream. If this pressure difference is of suflicient magnitude, thepower stream will be directed, in whole or in part, into the controlchamber 24. This causes the pressure in the control chamber to risealmost instantaneously. When the pressure in the chamber 24 reaches alevel which exceeds the pressure produced by the power stream, the powerstream will be forced to leave the control chamber 24 and return to itsoriginal exit path through outlet 22.

The power stream may be considered as representing a fluid outputpulse.The duration or width of this pulse is equal to the time duration ofundisturbed fluid flow, i.e. the time during which the power stream isbeing directed to the outlet 22. The pulse ends when the power stream isinterrupted, i.e. when the power stream is deflected into the controlchamber.

From the above description it will be clear that the power streamcontinues along its linear exit path, as long as the vacuum producedwithin the control chamber 24 is insuflicient to cause the power streamto switch, i.e. to cause it to deflect into the control chamber. It isseen that the smaller the volume of the chamber 24, the sooner thevacuum level at which switching occurs will be reached. In other words,the smaller the volume of the control chamber, the shorter will be thelength of 3 the output pulses. correspondingly, the shorter the lengthof the pulses, the higher will be the frequency of the generated pulses.Reversely, the larger the volume of the control chamber 24, the lowerwill be the frequency of the generated output pulses.

The volume of the control chamber 24 is determined by the position ofthe piston 35 within the chamber. The deeper the piston is positionedwithin the chamber, the smaller will be the volume of the chamber, and asmaller chamber results in higher frequency of the pulses gen erated. Itwill be appreciated that in this manner a gradual change of frequencymay be elfected over a wide range by the movement of the piston.

The frequency control of the output pulses by means of control chamber24, need not necessarily be by controlling the volume of the chamber. Analternative embodiment may involve an equally effective control byvarying the pressure within the chamber 24 while the volume of thechamber is maintained constant. Such a pressure control may be realized,for example, by means of a heater filament. Such a heater filament maybe located within the control chamber and supplied with a current toproduce heat. Heat developed by the filament will increase thetemperature and pressure within the chamber 24. The change in pressureaffecting the power stream will cause it to leave the chamber in themanner described. The amount of heat developed by the filament willdetermine the time required to build up the pressure Within the chamberto the level where switching of the power stream occurs.

Referring now specifically to FIG. 2, there is illustrateddiagrammatically a modification of the device illustrated in FIGS. 1 and1a. Like parts are indicated with the same reference numerals. Thedevices of FIGS. 1 and 2 are identical, except that the device of FIG. 2has an opening 44 adjacent the control region 42. The purpose of opening44 is to provide an auxiliary pressure on one side of the power stream42 to aid in the deflection of the power stream into the control chamber24. Thus, the opening 44 may be employed in various ways to in fluenceor control the frequency of the output pulse. The opening 44 maycommunicate with the atmosphere or with another suitable source ofpressure dependent upon the particular design of the system and theresults desired.

Referring specifically to FIG. 3, there is illustrated anotherembodiment of the present invention. Again, the parts are indicated withthe same reference numerals when such parts are similar to the onesillustrated in FIGURE 1. The device of FIG. 3 includes a loop 46branching off from outlet 22 at 48. The loop 46 establishes fluidcommunication between adown stream portion of the outlet 22 and thecontrol region 42. In this embodiment, a portion of the fluid outputfrom the outlet 22 is returned to the control region 42 through the loop46. This arrangement makes it possible to provide auxiliary momentum forthe switching action of the power stream 40 into the chamber 24.

It will be understood that modifications and variations may be effectedwithout departing from the scope of the present invention. For example,it will be understood that, although the devices illustrated anddescribed are basically of planar construction, a device according tothe invention may have a third dimension of substantial magnitude.Specifically, the control chamber need not be planar, but may becylindrical and be provided with a piston of conventional cylindricalform. Also, the number of power stream inlets, control chambers andpower stream outlets may be varied as a specific application of thedevice may require.

What I claim is:

1. A fluid device for producing output fluid pulse signals comprising amember having an outlet, a source of power fluid, means for directingsaid power fluid to said outlet along a normal path, a control chamberhaving a closed end, said control chamber having an open end, disposedadjacent said normal path of flow of said power fluid and incommunication therewith, said chamber being angularly disposed withrespect to said outlet so that said flow of power fluid in said outletcreates a partial vacuum in said control chamber to cause all of saidpower fluid to be deflected from its normal path into said chamber foran interval of time sufiicient to build up a pressure in said controlchamber to overcome said partial vacuum, and the angular disposition ofsaid chamber with respect to said outlet being such that said flow ofpower fluid is deflected back to its normal path to said outlet whensaid partial vacuum in said chamber is overcome by said pressure.

2. A fluid device as set forth in claim 1 wherein means are provided tovary the volume of said chamber whereby pulse signals of a variablefrequency may be produced at said outlet.

3. A fluid device comprising a member adapted to permit a fluid to passtherethrough, means for applying power fluid to said member, an outletfrom said member normally receiving said fluid, a fluid receiver beingclosed at one end, said fluid receiver having an open end adapted tocommunicate with said member so that fluid normally flows past said openend, said fluid receiver having a vacuum created therein in response tothe flow of said fluid past said open end to cause said fluid to switchinto said fluid receiver, said fluid receiver being responsive toreceipt of said fluid to increase fluid pressure theren whereby after apredetermined time said fluid is switched back to said outlet.

4. The invention as set forth in claim 3, wherein said means includes apiston adapted to be displaced within said receiver.

5. A fluid device comprising an inlet for providing power fluid, a firstoutlet in substantial alignment with said inlet, a second outletangularly disposed with respect to said first outlet and incommunication with said power fluid, and said second outlet having aclosed end to form an enclosed chamber to cause a partial vacuum to becreated therein to cause said power fluid when said power fluid isdirected out said first outlet to thereby switch from said first outletto said second'outlet and to return to said first outlet when saidpartial vacuum is overcome by said power fluid a predetermined timeafter said power fluid has been in said second outlet.

6. A fluid device comprising a member adapted to permit a fluid to passtherethrough, means for applying power fluid to said member, an outletfrom said mem ber disposed to receive said power fluid, a controlchamber constructed to communicate with said member and being responsiveto fluid flow out said outlet to switch all of said fluid into saidcontrol chamber, said control chamber being responsive to said fluidswitched into it to switch said fluid back to said outlet after apredetermined time.

7. The invention as set forth in claim 6 and means associated with saidchamber adapted to vary the volume thereof.

8. The invention as set forth in claim 6, and means associated with saidchamber to vary the pressure therein.

9. A fluid device comprising a member adapted to permit a fluid to passtherethrough, means for applying power fluid to said member, an outletfrom said member normally receiving said power fluid, an enclosedpressure responsive chamber angularly disposed with respect to saidmember and communicating with said member at a point where said fluidpasses through said member into said outlet such that a vacuum iscreated in said chamber when said fluid flows through said outletwhereby said fluid is periodically switched into said chamber when saidvacuum reaches a predetermined value and back into said outlet when saidvacuum is overcome when said fluid has been flowing into said chamberfor a pre- 3,053,276 9/62 Woodward 137-597 determined time. 3,072,1471/63 Allen et a1 137-815 References Cited by the Examiner FOREIGNPATENTS UNITED STATES PATENTS 5 1278782 11/61 France 3,001,539 9/61Hurvitz 137-8 M. CARY NELSON, Primary Examiner.

3,016,066 1/62 Warren 137-62414 3,024,805 3/62 Horton 137 81.5 ARNOLDGREGG, LAVERNE D. GEIGER,

3,030,979 4/62 Reilly 137624.14 1O Exammers'

1. A FLUID DEVICE FOR PRODUCING OUTPUT FLUID PLUSE SIGNALS COMPRISING AMEMBER HAVING AN OUTLET, A SOURCE OF POWER FLUID, MEANS FOR DIRECTINGSAID POWER FLUID TO SAID OUTLET ALONG A NORMAL PATH, A CONTROL CHAMBERHAVING A CLOSED END, SAID CONTROL CHAMBER HAVING AN OPEN END, DISPOSEDADJACENT SAID NORMAL PATH OF FLOW OF SAID POWER FLUID AND INCOMMUNICATION THEREWITH, SAID CHAMBER BEING ANGULARLY DISPOSED WITHRESPECT TO SAID OUTLET SO THAT SAID FLOW OF POWER FLUID IN SAID OJUTLETCREATES A PARTIAL VACUUM IN SAID CONTROL CHAMBER TO CAUSE ALL OF SAIDPOWER FLUID TO BE DEFLECTED FROM ITS NORMAL PATH INTO SAID CHAMBER FORAN INTERVAL OF TIME SUFFICIENT TO BUILD UP A PRESSURE IN SAID CONTROLCHAMBER TO OVERCOME SAID PARTIAL VACUUM, AND THE ANGULAR DISPOSITION OFSAID CHAMBER WITH RESPECT TO SAID OUTLET BEING SUCH THAT SAID FLOW OFPOWER FLUID IS DEFLECTED BACK TO ITS NORMAL PATH TO SAID OUTLET WHENSAID PARTIAL VACUUM IN SAID CHAMBER IS OVER COME BY SAID PRESSURE.